[XeTeX] problem getting small caps

[Mike Maxwell]

Ulrike Fischer wrote:
> You can use  \XeTeXtracingfonts=1 to get the path of the fonts xetex
> finds and uses in the log. 

Thanks--that tells me it's using the slightly older version of the 
Charis SIL font, but that version still claims to support small caps. 
(I also discovered that someone created both a ttF/ and a ttf/ subdir 
under /usr/share/fonts, but the contents appear to be identical.)

Let me try a different way to get at this problem.  I'd like to try 
using \fontspec to load some font that I know has small caps.

If I don't use \fontspec{Charis SIL}, xelatex picks some default font, 
and small caps work.  So I thought maybe I could explicitly tell 
\fontspec to load that font.  But afaict, the log file (with font 
tracing turned on) doesn't tell me what this default font is.  There's 
something about 'eu1lmr', but that doesn't appear to be an actual font.

Can anyone tell me what the xelatex default font is, and where the .ttf 
file is in the texlive distro?
-- 
    Mike Maxwell
    What good is a universe without somebody around to look at it?
    --Robert Dicke, Princeton physicist